1. Field of the Invention
The present invention relates to a biaxial hinge device and a mobile terminal device suitable to be applied to a mobile phone, a PHS (Personal Handyphone System) phone, a PDA (Personal Digital Assistant) device, a mobile game device, a notebook personal computer device, and so forth, which include a hinge unit enabling such operations as opening and closing of a case, for example. The present invention particularly relates to a biaxial hinge device having two rotation axes and a mobile terminal device, in which a space occupied by biasing members for biasing cam members used to regulate the rotation of the respective rotation axes is reduced to reduce the size of the biaxial hinge device, and in which a space for accommodating a harness or a flexible board for electrically connecting an electrical component provided to an upper case and an electrical component provided to a lower case can be eliminated to reduce the size of the hinge device.
2. Description of the Related Art
Japanese Unexamined Patent Application Publication No. 2005-198062 (pages 8 to 9 and FIG. 5, Patent Document 1) discloses a folding mobile phone having three functions, i.e., a function of opening and closing in a longer direction of an upper case, a function of opening and closing in a shorter direction of the upper case, and a function of folding with the upper case turned inside out.
The folding mobile phone includes a hinge unit configured to be divided into a first hinge unit and a second hinge unit. The first hinge unit includes a first rotating shaft for supporting the first hinge unit to be rotatable with respect to a lower case, and a second rotating shaft for supporting the second hinge unit to be rotatable with respect to the first hinge unit. The first rotating shaft and the second rotating shaft are provided to be perpendicular to each other. The second hinge unit includes a third rotating shaft for supporting the upper case to be rotatable with respect to the second hinge unit. The third rotating shaft is provided to be perpendicular to the second rotating shaft. With this configuration, the upper case can be rotated around the respective directions of three rotating shafts, i.e., the first rotating shaft, the second rotating shaft, and the third rotating shaft.